Process for the production of partial color selection pictures out of subtractive multicolor images



Feb. l, 1944. B. GASPAR 2,340,655

PROCRss FOR THR PRODUCTION OR PARTIAL COLOR SELECTION PICTURES OUT 0F SUBTRACTIVE MULTICOLOR IMAGES Filed March 25, 1957 2 Sheets-Sheet 1 Prg. E.

Feb. 1, 1944. B. GASPAR 2,340,656

PROCEss FOR THE PRODUCTION OF PARTIAL COLOR SELECTION 'PICTURES OUT OF SUBTRACTIVE MULTICOLOR IMAGES Filed March 23, 1937 2 Sheets-511661; 2

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Patented Fabi. 1, 1944 UNITE` orme Bela Gspr, Brussels-Forest, Belgium, or to Chromogen, Incorporated, ay corporation ci Nevada Application March 23, 1937, Serial No) '132,611 In Germany March 24, 1936 25 Claims. (Cl. 95-2) The subject oi the present invention is a process for the production of partial color selection pictures out of subtractive multicolor images. more particularly multicolor transparencies or translucent master images. Such a multicolor.

image contains colored monochromatic partial images covering and completing each other subtractively to a colored image. The necessity of producing the individual partial selections of such -multicolored images arises in various circumstances. For instance, the multicolor image may have been obtained directly in the camera and the individual partial selections may be required in order to serve as intermediary elements 'for lied uniformly by such shrinking and the single partial color selections produced from it are'in exact register, thereby permitting the production ofa'print of the multicolor image even if the original photograph-or the partial color selection images are no longerru able.

multicolor imag'e was originally produced. It is therefore not possible to reobtain the single color selection images used for the production of this complete image, without introducing the diillculty of departing from the complete multicolor print and therefore the prints produced later on do not suiiiciently resemble the multi-color image, the duplication of which ls intended.

Exact photographic printing cannot be performed unless the printing light acts on the master image to be printed with uniformf intensitythroughout the whole area. In passing through the master image, the intensity of this light is diminished in proportion to the graduation of opacity of the master image and thereafter acts on the printing layer with the graduation of intensity produced by the master image. For the same reason the print of a color selection in an individual layer is bound to be incorrect if the printing light, even though originally of uniform intensity, -is subjected to a. regional diminution of its intensity before reaching the selection imagewhich is actually to be printed. A diminu- It is understood that thefoliowing examples involve the usel of some of my earlier processes and materials 4such as those described and claimed in my patents, 1,956,122 and1,956,0l7 of April 24, 1934; Patent 1,985,344of Dec. 25, 1934; Patent 2,183,393 of Dec. 12,. 1939; Patent 2,029,775 of f Nov..12, 1935; 2,071,688.0f Feb. 23, 1937 and Patent 2,183,394 of Dec.fl2, 1939; and I Patent 2,137,336 of Nov. 22,1938.

It is known that the individual partial color selections of a. multicolorimagemay .be obtained by printing witha'. printing light whichis ab- -work is performed in a-most1-,exact.manner,'it

isinotpossible to'print partialselections of such a multicolor-.imageigtheabove mentioned way whicham vafsatisfactory reproduction oi those color-selection-pictures';by; means of which the tion of intensity of this' sort arises if an image of different color must be traversed by the printing light as most colors have the quality of absorbing to a'. certain extent even the light which they ought to transmit. For instance, a purplered dyestu diminishes the intensity of bluel printing-light although it theoretically ought to transmit this light without diminution. A bluegreen dyestu which ought to be transmittent for blueand greenis in reality not absolutely transmittent for these colors. Yellow and red dyestuffs show the most satisfactory attitude towards red light, which is almost completely transmitted by them. As a result of the above described phenomena, the blue light, for example,

which is to be used for the printing of a yellow master-image does not penetrate to the printinglayer withuniform intensity if it previously is led through a layer lying in front and containing a blue-green or a purple-red dyestui in an imagelike distribution. .el colored image lying behind the colored master-image has the same effect, as in this case a certain portion of the light which is to fall on the printing-layer is absorbed by this image, and therefore the correct photographic reproduction of the desired image on the printing-material is made impossible.

In accordance with this invention, the described image-like diminution in intensity of the printing-light is supplemented by an equal diminution of intensity graduated in the opposite sense. That is to say, if blue printing light, used acter of a negative as compared with the bluegreen image, if this image is assumed to be positive, and vice versa. In the simplest case, the compensation mask is of the same color as the image by which the intensity of the printing light is undesirably weakened, and in thiscase the distribution'of'color in the mask completes the image causing the undesirable eil'ect to a homogeneously colored area, when both are superimposed. The compensation mask may also be represented by a black and white image or an image in any other color which to a certain extent absorbs the printing-light. ,By means of the compensation mask, the local diminution of the intensity of the printing light is completed to a'uniform diminution of this light, whereby the correct printing of the partial images is made possible. Another way of carrying out the idea of the invention in practice is to make up for the undesirable deficit in the printing light by means of an additional illuminating of the print behind a compensation mask which represents a colored or black and white negative of the disturbing part image. In 'this case the intensity of the additional printing lightat all points of the 1mage must be equal to the diminution of intensity caused by the disturbing part images. case, the compensation applied is adjusted 1n such a manner as to equalize, either by addition or subtraction, the disturbing absorption of light by the other partial images.

Example 1 A multi-color image I shown in Figure 1, c onsisting of a purple-red colored positive part 1mage and a blue-green colored positive part image is used. From this a negative 2 of the bluegreen colored part image is produced by use of red printing light. This negative is dyed bluegreen at the exposed points and is then superposed with respect to the two color-film which is to be printed. Thereafter, the purple-red partial-image is printed by green light coming from iight source 3 through nlter 4. The blue-green areas of the multi-color image absorb a part of this green printing light, which absorption is, however, supplemented by the absorption of light by the likewise blue-green colored compensation masl; so that a imiform diminution of the intensity of the printing light .is attained. Therefore the presence of the blue-green partial image no longer has a detrimental effect on the printing process, except that the printing must be slightly intensied. As shown at 5, a print is obtained of purple-red'partial image.

In case three-color images in blue-green, magenta and yellow are printed, a blue-green as well as a purple-red mask are used; first, the blue-green mask is employed alone, and thereafter both masks are 4employed together when printing the yellow image as described above. 'lhisprooedureistobereoommendedforthe printingofmulti-colorimagesbysucoessiveuse In each color image.

of different printing lights on multi-layer material possessing several layers of different sensitivity. f

In the following, the invention is described by means of illustrations based on Fig. 2. For the sake of simpliication it is assumed that the multi-color image I0 from which the single part images'are to be reobtained, consists of a blank film II on which three colored letters A+, B+. and C+, appear as positives, B+ in purple-red, C+ in yellow, and A+ in blue-green.

this invention to the production of negativeA master images from a multicolor image is described.

A. Reobtaining of a master-image '0f the bluegreen colored part image contained in the multicolor image-The multi-color image III is first printed in the usual manner with red light or by use of a red-lter on to a red-sensitive or a panchromatic layer I2. The resulting image is developed and iixed, and thereafter represents a negative A- as shown at I3 of the blue-green colored partial image A+ contained in the multicolor image I0. y

B. Producing a master image of the purplered colored part-image contained in a multicolor image.-The multi-,color image III is printed in the usual manner by use of green light or a green-filter on a green-sensitive or panchromatic layer Il. Before developing and iixing this image, the negative A- which has been produced previously is printed on it in faint contrast by use of the same green printing light with which the multi-color image has been printed. Or, alternatively the negative may be colored blue-green at the exposed points and may be printed in superposition withV the multi- The print is then developed and xed, thereby becoming a negative B- as shown at I5 of the purple-red colored partial image B+ contained in the original multi-color image. C. Producing a master image of the yellow colored partial image contained in the multi-color image-The multi-color image I0 is printed with blue light on an ordinary photographic layer I6 in the ordinary manner. However, the layer is not developed, but first the negative'A- and thereafter the negative B- are additionally printed on this layer. In doing so, the intensity of the printing light is regulated in such a man` which may either be used as such, if in the further course of the process negative master images of this kind are required, or can be converted into positive master images as shown at It, I9 and 2l in the usual manner, if required. The

three master images A-, B- and C- or the pomtives A+,-B+ andC-lproduced from them may be converted into dyestuif-images. The dyestuiftobeuseddepends onthemannerinwhich the printing layers are sensitized on' to which Athe master-images are subsequently printed. In any case, a dyestuif is usedwhich abmrbs light-rays to which the respective printing layer is sensitive.

' Example 3 The negative A- produced in accordance with Example 2, corresponding to the blue-green parother hand, this red image may also be `employed later for other purposes, for example to print the partial image A- on a layer sensitive to green or blue.

The same holds good for the negative B-, winch may for instance be of a yellow, green or red color and may serve the same purposes as the black and white negative.

Erample 4 tographic layer, a positive A+ is produced. This positive A+ is used in further printingprocesses which require positive master images of the color selection pictures, for instance for processes in which a dyestui is produced at the non-exposed places of the print or in whicha dyestui which .index Number 365) andthe third sensitive to quired for the processes'mentioned above is obtained.

The three positive .master images A+, B+ and C+ may for instance be printed on a multilayer material not shown consisting of` three layers superimposed on each other, one sensitive to blue and dyed purple-red by diamine -iast Pink G (Ullmann Enzyklopdie der Technischen Chemie, 2nd

edition, volume 3, page' 647),` thesecond sensitive` to red and dyed yellow by chrysophenine (color infra-red and dyed blue-green by diamine pure was originally present is destroyed at the exposed places.

B. Reobtaim'ng the master image of the purplered colored partial-image from the multi-colorl image- The multi-color image is printed on a green-sensitive or panchromatic layer by means of green light. The print is then developed and iixed. In this manner a negative image B- of the purple-red colored partial-image contained in the original is obtained, which negative is howl ever not quite correct due to the fact that the printing lightdoes not fall on the colored image B+ with uniform intensity as it is subjected to certain influences, originating for instance from the blue colored part-image. This negative B- is printed on an ordinary lm. Before developing the print the positive A+ is additionally printed on it in low intensity. After developing it is xed and serves as the .second positive master image B+ for above described processes.

C'. Reobtaimng the master image of the yellow colored partial-image froml the multi-calm' image-The multi-color image is printed on an ordinary photographic layer by means of blue light. Thereupon the image is` developed and xed. In this way a negative C- of the yellow colored partial image contained in the original is obtained, which, however, for the same reasons as mentioned in connection with image B-, is not a correct reproduction. This 'negative is printed on an ordinary nlm. However this film is not developed until the positive A+ and the positive B+ have been additionaly printed on the same material in low intensity, the positive A+ being printed with greater intensity than the positive B+. Then the nlm is developed and xed. whereby the third positive master image C+ reblue FF (color indexV Number 518). The master image A+ is printed on tothe blue-green dyed -V layer by infrared light, the masterimage B+. ori-- the purple-red layer by blue light, and the master image C+ on the yellow dyed layer by red light. The nlm is then developed, fixed and treated by a 5% thiocarbamide' solution containing` also 21/2% citric acid. Thereafter it is bleached by a solution of copper chloride and ilxed by a xing solution. .'Ilieimage obtained after this treat'- ment is a color-true reproduction of the original multicolor image.

supposing that the original multi-color image does not correspond in its colors to the natural object, but that for instance the blue-green co1- ored partial image represents the green selection of the natural object, whereas the purple red im- Example 5 Three single master images are to be produced vof a multi-color image, containing three partial images in superposed layers in the three colors purple-red, blue-green and yellow, andl these are to be printed on a similar material. Referring again to Fig. 2 and the multi-color image I0 which is to be reproduced; the positive nlm 2| which is to be used for printing consists of three layers, i. e., a blue-green colored and blue-sensitive emulsion on one side of the support and a yellow-colored red-sensitive emulsion on the other side of the support, the latter' layer being covered by a purple-red colored and blue sensitive emulsion. The images I8, I9 and 20 are printed on this material. from both sides by use ofA blue light for the outside layers, and the middle layer is simultaneously printed on by wa'yof red light traversing. the purple-red layer. After the silverimage has been produced, the dyestui is .destroyed at the silver places. The master images used for printing on the material` 2l must be positive images of the three partial selections and may be three master images in colors comple-A mentary to the sensitivity of the layers in which they are to be printed. In such case the two images which are to be printed on the two exterior blue sensitive layers. (one of which is colored purple-red and the other blue-green) are colored yellow, whereas the image which is to be printed on the middle layer is of a blue-green color. For producing these 'three-colored master images, three individual layers are employed, i. e.,

dyed layer I6 sensitive to green and blue. The

red light in the manner described above.

two yellow layers may be sensitized for both green and red, in which case it is possible to carry out the following process by use of only two different printing materials.

(1) First the multicolor image is printed on the yellow-colored red sensitive printing layer I2 by red light, whereupon the print is developed and A same material I4 by the same light. This print is then developed and fixed and thereuponshows a black silver image on a yellow background as shown at I5,.on which those places which correspondto the purple-red partial selection of the multicolor image I are transparent (i. e., yellow).

(3) The multicolor image is then printed by blue light on the blue-green dyed layer I6 which is sensitive to blue and green.- In addition to that, the negative silverimages I3 and I5 previously obtained, are printed on the same blue-green dyed layer I6 by use of green light. This iiim is then developed and xed. A black silver image is obtained as shown at II, which is transparent (blue-green) at those places corresponding to the yellow partial selection ofv the multicolor image.

(4) The three silver images i3, I5 and I 'I produced in this manner on the two yellow iilms and the blue-green iilm are thereupon treated with a dyestufI-destroying solution, e. g. with a 5% thiocarbamide solution containing in addition 21/2 citric acid, and converted in the usual manner into dyestuff images. In this manner, the positive intermediary master images shown at I8, I9 and 20 are obtained, from which the yellow images are then printed on the multilayer material 2i by blue' light and the blue-green wiltlh e dyestui is simultaneously destroyed in all three layers of the multilayer material by bathing in a thiocarbamide-solution of above mentioned composition and the further treatment results in a` print 22 which is identical to the multicolor image I0.

` Example 6 The multicolor `image of which individual partial selections are to be produced contains positive partial images in blue-green and yellow colors, of which the yellow image represents the red selection of the photographed object and the blue-green image the green selection of this object. Such multi-color images may be obtained assording to my copending application i437, iiled January l1, 1935, by photographing with a bipack, the iront nlm of which is not colored and is sensitive to blue, whereas the back iilm bears two superimposed layers, one dyed yellow and sensitive to red, and the other dyed blue-green and sensitive to green, and thereafter locally destroying the dyestui at the exposed places after exposure and development. After separation of the b ip'ack, the rontalm is developed separately to a negative or to a positive. By use of red printing light the 2-color image in yellow and ,blue green contained 1n the back'iiim is printed on a printing material having yellow colored red sensitive layer. 'Iiiereafter the printing material is developed and fixed whereupon it contains a black silver image in which the parts corresponding to the bluegreen parts of the rear lm of the bi-pack appear yellow.

By use of blue light the back film is printed on a printing material having purple-red dyed layer sensitive to blue and red and the developed and ilxed image on the yellow printing material is also printed on this purple-red layer by use of red light. Then both the yellow printing film and the purple-red printing film (after having been developed) are bathed in a thiocarbamide solution of the above mentioned composition. After destruction of the dyestui and removal of the remaining silver, a yellow print of the bluegreen partial image contained in the rear illm of the bi-packrlm, that is to say of the green selection, is obtained. 0n thev purple-red printing material, a purple-red image of the yellow colored partial image registered on the rear nlm of the bl-pack, that is to say of the red selection, is obtained. These master images may be printed on the two exterior layers of the threelayer material 2| described in Example 5 in the same manner as explained in the previous example, the yellow colored image (green selection) being printed on the purple-red layer, the purple-red colored image (red selection) on the blue-green layer of the multi-layer material, the latter layer in this case having to be sensitive not only to blue but also to green. 'I'he blue selection produced Aon the colorless front nlm is printed from a positive master image on to the middle layer of the positive three-layer illm by means of red light.

In case, in the described example, the bluegreen layer of the positive lm is not to be made sensitive to green, and if it is desired to use a completely identical positive material, as shown at 2|, a colorless panchromatic or red and blue sensitive iilm is used for the master image of the yellow colored partial image, instead of a purple-red colored layer. The two-color image produced on the back iilm of the bi-pack is printed on this material by means of blue printing light, whereupon the black and white image of-the blue-green partial image, produced on the yellow master image is additionally printed on the same material by red light. This negative master image must then be transformed into a positive and is printed by blue light on the blue-green layer of the three-layer material. The negative may also be dyed by a yellow dyestuff after producing the silver images in the layer and converted directly into a yellow positive by treatment with above-mentioned thiocarbamide solution. This yellow positive is then printed on the blue-green layer of the threelayer material by blue light.

In the preceding example the silver image originally produced by printing into the colored layer served as a compensation mask and thereafter was used for the destruction of the dyestull at the points where silver is present thereby producing from the mask a lreversed dyestuiimage constituting the required master image.

A silver image originally produced by printing into ordinary colorless layers, may also serve as a compensation mask and thereafter be transformed into a reversed image, constituting the required master image. In this oase the unexposed silver halide is allowed to remain in the image during its use as compensation mask and the reversed image is produced afterwards-lay disselving the silver image end developing .the silver halide to form the master image. The

aas-aoco general theory of the above examples may be the printing material. `slm isdeten'nined by* the intensity of the printing light and the qualities in the printing layer. At those places of the image however, the geometric coordinates of which are :c and y and at which absorbing dyestuils are present, the blackening is diminished to the extent determined by the degree of absorption of the colors present. The diminution in intensity of printing-light I used in printing the part-image constituted by dyestuff A is designated by the term A1 .'c 111/. At this point the image may be defined as sorption produced by dyestu A at the point r, y; B lx, y/ represents the absorption at the same point of vthe image by dyestui B'of the printing light used for printing partial image B.' The term EB represents the ratio between the` absorption of dyestuil B in the printing light used for printing the partial image dyed by dyestuil' A) and the greater (absorption of this dyestuil B inthe printing light used for printing 3 It results from these formulae that the coinpensation required for the one image is whereas the compensation required for the other image is expressed by the term E4 A /a:, :z//. In

in more than one oi.' these properties, or even in all of them. l

This manner of executing the invention is first to be described by way of an example, and thereafter the possibilities of varying the procedure are to be' described, by which the principles in accordance with which the invention may lbe applied in other cases will easily be recognized.

Example 7 xIn order to produce on separate supports the individual color selection pictures of, for instance, a two, color image consistinggof a yellow colored partial image and a blue colored partial image, the two color image is rst printed with red light on a lm sensitized to red or panchromat- "ically sensitized, wherebya print of the bluegreen colored part image of themulticolor image is obtained. If'the latter Vwas a positive, the intermediate print obtained will be a negative.

Thereafter the multicolor image is printed with blue light on a two-layer intermediate printing material. This two-layer printing material maybe composed in various ways, several of the possibilities of composition being illustrated in the'attached drawings. For instance, the intermediate printing material may be made up as illustrated in Fig. 3, of twov blue-sensitive layers, one` on each side of the support, the lat- Vter being as thin as technically possible. This support is dyed intensely yellow, so that it is nontransmittent for blue ra'ys striking the material from either `o1' the two sides. Another possibility 5 is to separate the twol blue-sensitive emulsions,

as is illustrated in Fig. 4 by coating the support' with a gelatine layer dyed yellow by admixture of 2 gr. of tartrazine per sq. metre of the surface. This coating must be decolorizable by washing.

Of the two blue-sensitive emulsions, one is 'dyed sumciently intensely by a yellow dyestuff, for instance by 0.5 gr. of Chrysophenine G to produce prints by blue light which are of a very much slighter contrast vthan the images prodit duced by blue light of approximately the accordance herewith, the latter is superprinted on the former in the ratio Ea and the former is superprinted on the latter in the ratio EA. In this manner the images are corrected, however, they are to a slight extent weakenedin intensity.

This decrease in intensity maybe compensated' 'used as printingmaterial. One of the layers is used for registering the desired color4 selection 55 tent, e. g. 2 g. of' silver bromide per m.2.

latter produces a print very much softer in consame time intensity value, in the colorless layer l on the other side of the material. The' same effect may be obtained by employing colorless silver halide layers, one of which is of a different composition than the other. For instance, as is shown in Fig. 5, an ordinary silver halide emulsion layer containing, e. g. 8 g. of s ilver bromide per'm.2 may be combined with a silver halide emulsion layer with reduced silverV contrast than the former.

The two color image, from which the blue-green partial image has been printed beforehand is 6g printed by blue printing light layer against layer, on the colorless side of the intermediate printing film, that is to say, on the side of the film bearing the emulsion producing the greater contrast when printed upon. The latent image v 65 of an incorrect print of the yellow part image of image printed from the multicolor original,

' say, the layer used for printing the compensa- Vtive image, diiers from the layer on which the selection itself is printed in color sensitivity, in

' the two color image is thus obtained. If thek latter was a positive, the latent image will be a negative.

. The previously produced negative selection of 7 0 the blue-green partial image of the multi-color image is laid layer against layer on the yellow '(5 latent positive image of low contrast of the blue- 5 contents ot silver, in gradation, or in coloring or The' green partial image of the two color image is obtained.. This positive of low contrast represents a correction oi' the errors which have arisen in printing the yellow partial image. After developing, which can be done separately on each side of the intermediate printing lm, a correct negative reproduction of the yellow partial image contained in the original is obtained. e

For printing the incorrect intermediate print on to the one layer and the print serving as corrective image on to the other layer of the multilayer intermediate printing iilm, a printing machine provided with registration pins should be employed. A machine equipped in this manner -should likewise be employed in producing intermediate prints on the one-layer printing material. In this manner, the individual part-images lmay be printed into each other in exact register and also exact register of the image which is to be correctedand of that serving as corrective is assured. By the fact that these .two images, that is' to say the one which is to be corrected and the one serving ascorrective, are registered on the same intermediate master image, the danger of unequal shrinking of the two images is avoided. Such unequal shrinking can occur ,if the corrective image is printed on a separate iilm. Another advantage of combining the image which is to be corrected with the corrective image on one and the same printing nlm is the simplification of the further procedure, as in this manner both images may be developed at the same time, so that the desired diii'erences in contrast are produced automatically, provided that the layers of the intermediate printing material are balanced against each other accordingly.

'I'he color selection images printed on the intermediate printing material may be employed in any way whatsoever, eitherdirectly or indirectly, for producing multi-color prints. However, attention must be paid to the fact that the presence of the yellow color in the two-layer intermediate printing material in accordance with Figs. 3 and 4 excludes the employment of blue light inthe further treatment of the material.

In other words, the yellow color must either first be removed or the lm must be printed by use of green or red printing light.

'I'he described example, in which the incorrect print of the partial image in question, as well as the image serving as corrective image, are printed on the multilayer intermediate printing material as black and white images represents the simplest form of application of the use of multilayer material for producing corrected selection pictures. It is for instance possible according to the invention, to produce either the print of theA image which is -to be corrected or the partial image serving as corrective image or bothA of these prints as colored prints. AFor instance, the silver image 'produced in the yellow dyed layer in accordance 'with Example '7 may be converted into a yellow dyestul image by destruction of the dyestui present. If the dyestui destroying agent, for instance an acid solution of thiocarbamide (in accordance with U. S. Patent No. 2,020,775 issued October 30, 1931), acts at those places of the image where silver is present and therefore produces a reversed image oi the partial color selection printed as a corrective image', then in- I stead f using a negative oi' the blue-green partial image contained in the original to p rint on the yellow. side of the two-layer intermediate printing material (i. e., the side producing prints of soft contrast). as described above, one'must produced in this manner shows, after destruction of the dyestui and removal of any silver, which might still be present in the layer containing the dyestui image, the desired negative partial selection in the form of a silver image on one side and a positive dyestuii image serving as a correction Vof this print on the other. An intermediate print of this kindl corrected by a dyestuli compensation. picture is printed by use of light for which the respective dyestuil' is more or lessv non-transmittant, for instance blue light is used in the case of a yellow dyestuif image, and green light in the case of a red dyestui image.

An intermediate printcorrected by a yellowA dyestuff compensation image and representing the red selection of the original object may be printed directly on to a blue-sensitive layer of blue-green color. In this case colorless supports are used, or ii yellow filter-layers are employed, these must be decolorized before the printing is performed.

If the ilnal print is desired in the form oi.' a positive master image, positive intermediate prints are produced from the negative intermediate prints obtained. For producing such further intermediate prints as may be required, an intermediate print consisting of black and white images or preferably intermediate images produced on the multi-layer material described above in which the corrective age is represented by a dyestufl picture may be used. In this case it is possible to regulate the contrast or the correct coverage of the corrective image with the image to be corrected once more by choosing a printing light which is absorbed by the color of the corrective dyestuif image to the extent desired. A second rgulation of the contrast may be obtained by printing the silver image con-v tained in the two-layer intermediate printing material for a longer time than the dyestul image present on the other side of the material. For example by switching over from a printing light color which is absorbed bythe dyestu' to a printing light of a color which is transmitted by the dyestuff in question, the printing elect of the dyestui image is stopped after a predetermined time. This method is applied in case the corrective image is too intensely colored and the basic negative is to be accentuated in comparison to the utter.

In case the primarily produced intermediate for producing a further intermediate print, the

two-layer intermediate printing material described may be used for the further intermediate prints and all of the individual partial selections may iirst be printed on ordinary printing material without employment lof the correcting images, these images being employed when the iinal intermediate prints are produced on the multilayer material described.

Example 8 the middle layer is yellow and sensitive to red.

The image is to be produced by destructionof ing the latter into the red sensitive yellow layer of the nal three-layer material.

In producing the two images as described above in the two-layer intermediate printing material,

ing, the nlm on which a print is to be produced y with red light is arranged layer against layer on the blue-green side of the multicolor image, and the lms on which printing is to. be performed with green and blue lightare laidlayer against layer on the purple-red side of the master image. The negative intermediate print produced by red light is printed directly layer against layer on to another` one-layer film, producing a positive whichis thereupon printed on to the blue-green layer of the final multilayer printing material 2lshowninFlg.2.

For the purpose of producing secondary intermediate prints ofthe two negative intermediate prints produced with green and blue light, a twolayer nlm as shown in Fig. 6 is used as a printing material. The support is coated with a. layer printed into the material, in which case,.however, the printingis performed by laying the positive 'layer against layer on to the intermediate print-` v,ing material. The contrast of color intensity lon the image may be regulatedvby adjusting the dyed green by a mixture of chrysophenine G f (Schultz l. c. No. 726) and Diamine pure blue FF (Schultz l. c. 510) and sensitized to green by the aid of erythrosine (Schultz '173), towhich a second coating is added consisting of a plain emulsion sensitive to blue. The negative produced by green light is printed on the material shown in Fig. 6 by blue light, the two illms being arranged layer against layer whereby a latent image is obtained in the upper layer which is however not correct. Thereupon a previously produced negative corresponding to the bluegreen partial image of the original is laid upon the two-layer intermediate printing material, the support of the negative being placed directly on 'the upper layer of the two-layer material, and

is printed into the lower layer by use of green light. 'I'hereby a latent positive image is obtained in the green layer. Thereafter, the film is developed and xed in the usual manner and is then bathed in a solution of thiocarbamide. By this bath, the dyestuif in the lower layer is destroyedV and the silver is dissolved. In the upper layer, however, which contains more silver, the

silver image is only slightly affected. In theV upper layer therefore a positive black silver image remains, whereas in the lower layer a negative green colored dyestuif image is obtained. This intermediate positive is printed on the bluesensitive purple colored layer of the iinal threelayer material by use of blue light, for whichv purpose it is laid directly with its layer against the purple layer of the printing material.

The intermediate print for the third partial image is produced in exactly the same manner as has been described above. This intermediate print is laid layer against layer on to the purple side of the nal 3-layer printing material and is printed with red light, the final print being produced in the yellow layer of the material. As concerns the further treatment of the multi-layer material, it is now only necessary to destroy the dyestuif in the silver regions in the usual manner by use of, for instance, thiocarbamide, whereby the nal multi-color image is obtained.

In the example described above only one single corrective image was printed into each of the two multi-layer intermediate printing films for compensation purposes. However, a previously produced and corrected intermediate print as described above may in addition be printed into the multi-layer intermediate print before printthe method employed may deviate in -various ways from the manner of procedure laid down in above examples. For instance, in Example 8 the corrective image may be produced as a silverimage of low contrast instead of a dyestuif image, if, instead of the negative image corresponding to the kblue-green partial color selection. of the original, the positive produced from this negative is printing light used accordingly. If a corrective image showing a hard contrast is desired, more green light is used; onthe other hand, if an image of softer contrast is desired, more red lightl is used. In this case the treatment by thiocarbamide is replaced by a treatment with a 2% solution of sodium hydrosulphite, this treatment being continued long enough to completely bleach out all of the dyestui present in the lower layer of the two-layer material. In case a master ,image on an opaque support is to be printed`- the-manner of procedure described in Example 8 may be followed.

Other examples of the two-layer intermediate printing material described in this specication are indicated in Figs. '7 and 8. vThe' material represented by Fig. 8 comprises two supplemen.-

tary layers, bothl of which contain only small proportions of silver, these proportions diiering fromeach other. This material is to be recomn mended if it is necessary to produce more than one corrective image and if the corrective images produced are to show different degrees of contrast. By using this material in addition to the print of normal contrast, two further corrective prints of weak contrastare obtained in the two supplementary layers. In general, thatis to say in the present example as well as in the examples described in the foregoing, ,the corrective layers are produced or developed in such a manner that the gamma infinite of the layer intended for the corrective image is at the most half the value l of the gamma infinite of the other layer.

The words positive and negative are defined as meaning the mutual relationship of the l respective images thus designated, i. e., that the points of maximum density of the respective images are inverse with respect to each other.

Instead of employing separate layers coated on each other, emulsion particles of different sensitivity, coloring or contrast' may be mixed with each other and coated on the support as a single layer.

In addition to that, in accordance with the invention, the intermediate printing material may be composed by combining an ordinaryk emulsion with an emulsion which directly produces positive images by simple development.

. The two emulsions are made sensitive to different colors, the incorrect image and the image serving as corrective being printed into the material from positive master images by use of appropriate printing light. In this way, -the incorrect negative print is obtained in direct combination with the image serving for correction of this print on one single nlm.

Insteadof employing the contact printing method mentioned in the vabove examples, the

optical printing method may be employed in all of the processes.

By the present invention correct partial selection pictures will be obtained in each case in which the latitude of the correcting print combined with the print to be corrected is the same as the latitude of exposure of the latter i. e., when the gradation of densities of the correcting print is of opposite sign to the gradation of densities in the part image to be corrected. Of the combined images the correcting image has a maximal density which is as many times lower than the maximal density of the image to be corrected as the absorption of the disturbing dyestuil in the printing light used for printing the desired image is lower than the absorption of the dyestuif forming the desired image. This meansalso that the gamma of the correcting image and the gamma of the image to be corrected are in the same proportion to each other as the maximum abscrptions of the disturbing dyestui in the image and the dyestui of the part image of the multi-color image to be printed.

W'hat I claim is:

1. A method of producing color selection pictures from a subtractive multicolor image containing the individual color selection pictures each in a different coloring matter, one ofsaid color selection pictures being a part image-recorded by a dye of such absorption characteristics that light which said dye absorbs to a substantial extent is also absorbed by said multicolor image as a result of the absorption of a second differently colored part image, which comprises forming a developed negative image of only the second named part image in a separate printing material,` printing a negative image in sult of the absorption of said second printing light by the color of said differently colcred part images, and simultaneously developing the negative and positive image in said second lightv sensitive material.

3. A method of producing color selection pictures from a subtractive multicolor image containing the individual color selection pictures each in a.diierent coloring matter, one of said color selection pictures being a part image recorded by a dye of such' absorption characteristics that light which said dye .absorbs to a substantial extent is also absorbed by said multicolor image as a result of the absorption of a second diierently colored part image, which comprises printing a negative image of only said second named part image in a light sensitive layer with colored light absorbed substantially alone by the color of said second named part image, developing the print thus obtained, printing a negative image in a second light sensitive material with a diierently colored printing light absorbed by the color of not only the rst named part image but also to a lesser extent by the color of said second named part image, and separately exposing the second light sensitive material behind the negative print of said second named partv image to produce a positive image in said second light sensitive material which compensates for the undesirable image obtained therein as a result of the absorption of said a second light sensitive material with a colored printing light absorbed by the color of not only said rst named part image but also to a lesser extent by the color of said second named part image, and separately exposing thr second light sensitive material behind the negative print of said second named part image to produce a positive image in said second light sensitive material which compensates for the undesirable image obtained therein as a result of the absorption of said second printing light by the color of said second named part image and simultaneously developing the negative and positive image in said second light sensitive material.

2. A method of producing color selection pictures from a subtractive multicolor image containing the individual color selectionpictures each in a different coloring matter, one of said color selection pictures being a part image recorded by a dye of such absorption characteristics that light which said dye absorbs to a substantial extent is also absorbed by said multicolor image as a result of the absorption of one or more differently colored part images, which comprises forming a developed negative image of each of said differently colored part images in a separate printing material, printing a negative image in a second light sensitive material with a colored printing light absorbed by the color of not only said ilrst named part image but also to a lesser extent by the color of said differently.

the secondlight sensitive material behind the negative prints of said differently colored part images to produce a positive image in said second iight sensitive material which compensates for the undesirable image obtained therein as a resecond printing light by the color of said second named part image and simultaneously developing the negative and positive image in said second light sensitive material.

4i. A method of producing color selection pictures from a subtractive multicolor image containing the individual color selection pictures each in a diierent coloring matter, one of said color selection pictures being a part image recorded by a dye of'such absorption characteristics that light which said dye absorbs to a substantial extent is also absorbed by said multicolor image as a result of the absorption oi a second differently colored part image, which comprises printing a negative image of only said second named part image in a light sensitive layer with colored light absorbed substantially alone by the color of said second named part image, developing the print thus obtained, printing a negative image in a second light sensitive material with a differently colored printing light absorbed by the color of not only the iirst named part image but also to a lesser extent by the color of said second named part image, and subsequently exposing the second light sensitive material behind the negative print of said second named part image to produce a positive imageA in said second light sensitive material which compensates for the undesirable image obtained therein as a result of the absorption of said second printing light by the color of said second named part image and simultaneously developing the negative and positive image in said second light sensitive material.

-5. A method of producing color selection pictures from a subtractive multicolor image containing the individual color selection pictures each in a different coloring matter, one of said color selection pictures being a part image recorded by a dye of such absorption characteristics that light which said dye absorbs to a substantial extent is also absorbed by said multicolor image as a result of the absorption of a second differently colored part image, which printing a negative image in a second light sensitive'maierial with a colored printing light absorbed by the color of not only the rst named part image but also to a lesser extent by Vthe color of said second named part image and exposing the second light sensitive material behind the colored negative print of said second named part image of the multicolor image to produce a positive image in said second light sensitive material which compensates for the undesirable image obtained therein as a result of the absorption of said second printing light by the color of said second named part image and simultaneously developing the negative and positive image in said second light sensitive material.

6. Amethod of producing color selection pictures from a subtractive multicolor image containing the individual color selection pictures each in a different coloring matter, one of said color selection pictures being a part image recorded by a dye of such absorption charaoteristics that light which said dye absorbs to a substantial extent is also absorbed by said multicolor image as a result of the `absorption of a seco'nd diierently colored part image, which comprises forming a negative image of only the second named part image in a separate printing material and transforming said image into a dyestui image by coloring the exposed parts the same color a's said second named part image, printing a negative image in a second light sensitive material with a colored printing light absorbed by the color of not only the iirst named part image but also to a lesser extent by the color of said second named part image and exposing the second lightysensitive material behind the colored negative print of said second named part image of the multicolor image to produce a positive image in said second light sensitive material which compensates for the undesirable image obtained therein as a result of the absorption of said second printing light by the color of said second named part image and simultaneously developing the negative and positive image in saidsecond light sensitive material.

7. A method of producing color selectionpictures from a subtractive multicolor image ccntaining the individual color selection pictures each in a different coloring matter, one of said color 'selection pictures being a part image recorded by a dye of such absorption characteristics that light which said dye absorbs to a sub- -stantial extent is also absorbed by said multicolor image as a'result of the absorption of a second differently colored part image, which comprises forming a negative image of only the' second named part image in a separate printing material and transforming said image into a dyestuff image by coloring the exposed parts the same color as said second named part image, printing a negative image in a second light sensitive material with a colored printing light absorbed by the color of not only the first named part image but also to a lesser extent by the color of said Asecond named part image and exposing 'the-second light sensitive material behind the colored negative print oi said second named partimage of the multicolor image to produce a positive image in said second light sensitive ma.- terial which compensates for Ithe undesirable image obtained therein as a result of the abasiatico sorption of ,said second printing light by the color of said second named partimage, said last mentionedrexposure being made simultaneously with the printing of said negative print of said iirst named part image into said second light' A sensitive material, and simultaneously developing the negative and positive image in said second light sensitive material.

8. A method of producing colork selection pictures from a subtractive multicolor image containing the individual 4color selection pictures each in a diiierent coloring matter, one of said color selection pictures being a part image recorded by a dye of such absorption characteristics that llight which said dye absorbs to a substantial extent is`also absorbed by said multicolor image as a' result of the absorption, of a second differently colored part image, which comprises forming a negative image of only the second named part image in a separate printing material and transforming the image into a dyestuff image by coloring the exposed parts with a dyestuff of such color and such intensity that the absorption of saidimage i'or light of a predetermined Wave length in the main absorption range of' the dye forming said iirst named part image is substantially equal and opposite to the absorption of said second named part image for the same light, printing a negative image in a second light sensitive material with a colored printing light absorbed by the color of' not only the first named part image but also to a lesser extent by the lcolor of said second named partl image and exposing the second light sensitive material behind the colored negative print of said second named partimage of the multicolor image to produce a positive image in said second light-sensitive material which compensates for the undesirable image obtained therein'as a result of the absorption of said second printing light by the color of said second named part image, said last mentioned exposure being made with light of said predetermined wave length and simultaneously with the printing of said negative print of said iirst named part image into said second light sensitive material, and simultaneously developing fthe negative and positive image in said second light sensitive material.

9. A method of producing color selection pictures from a subtractive multicolor image containing the individual color selection pictures each in a different coloring matter, one of said color selection pictures being a. part image recorded by a dye of such absorption characteristics that light which said, dye absorbs to a substantial extent is also absorbed by said multicolor .image as a result of the absorption of a second diierently colored part image, which comprises forming a negative image of only the second named part image in a separate printing material and transforming the image into a dyestui image by coloring the exposed parts the ysame color as said second named part image,

tive and positive image in said second light sen-- sitive material.

10. A method of producing color selection pictures from a subtractive multicolor image-containing the individual color selection pictures each in a different coloring matter, one of said color selection pictures being a part image recorded by a dye of such absorption characteristics that light which said dye absorbs to a substantial extent is also absorbed by said multicolor image as a result of the absorption of a second differently 'colored part image, which comprises forming a developed negative image of only the second named part image in a separate printing material, printing a negative image with a colored printing light absorbed by 'the color of not only the lfirst named part image but also to a lesser extent by. the color of said second named part image on a second light sensitive material and separately exposing the seceach in a dierent coloring matter, one of said color selection pictures being a part image recorded by a dye of such absorption characteristics that light which said dye absorbs to a substantial extent is also absorbed by said multicolor image as a result of the absorption of a second differently colored part image, which comprises forming a developed negative image of only the second named part image in a light sensitive layer of a separate printing material, said layer being colored by a dyestuff which is transmittant for light used in printing said negative image, printing a negative image with a diierently colored printing light absorbed by the color of not only the rst vnamed part image but also to a.lesser extent by thecolor of said second named part image on a second light sensecond named part image with light transmitted by the dyestuff used for staining the same to produce a positive image in said second light senond light sensitive material behind the negative print of said second named part image to produce a positive image in said second light sensil 4each in a different coloring matter, one of said color selection pictures being a part image recorded by a dye of such absorption characteristics that light which said dye absorbs to a substantial extent is also absorbed by said multicolored image as a result of the absorption of a second differently colored part image, which comprises forming a developed negativeimage of only the second named part image in a separate printing material, printing a negative image with a colored printing light absorbed by the color of not only the rst named part image but also to a lesser extent by the color of said second named part image onto a second light sensitive material andexposing the second light sensitive material behind the negativel print of said second named' part image to produce a positive image in said second light sensitive material which compensates for the undesirable image obtained therein as a result of the absorption of said second printing light by the color of said second named part image, simultaneously developing the negative and positive image in said second light sensitive material and thereafter transforming both prints into positives and selectively printing the positives thus obtained on the layers of a multilayer light sensitive mateial which layers are complementarily dyed with respect to the color selections registered in the original color selection pictures, developing the multilayer material and destroying the dyestuil in the multilayer print at the points of sitive material .which compensates for the undesirable image obtained therein as a .result of the absorption of said differently colored printing lightby the color of said second named part image of said multicolor image, simultaneously developing the negative and positive images .in said second light sensitive material and transforming both prints into colored positivesfselectively printing each print into a layer of a multilayer light sensitive material, 4and converting them into dyestui images.-

13. A method of producing color selection pictures from a subtractive multicolor image containing the individual color selection pictures each in a diierent coloring matter, one of said color selection pictures being a part image recorded by a dye of such absorption characteristics that light which said dye absorbs to a substantial extent is also absorbed by saidmulticolor image as a result of the absorption of a second diierently colored part image, Winch comprises forming a developed negative imageI of only the second named part image in a light sensitive layer of a separate printing material, said layer being colored by a dyestuff which is transmittant for light used in printing said negative image, printing a negative image with adiflerently colored printing light absorbed by the color of not only said first named part image but also to a lesser extent by the color of said second named part image on a second light sensitive material, exposing the second light sensitive material behind the negative print of said second named part image with light transmitted by the dyestui used for staining the same to produce a positive image in said second lightV sensitive material which compensates forthe undesirable image' obtained therein as a result of the absorption of said differently colored printing light by the colorof said second named part image of said multicolor image, thereafter simultaneously developing the negative and positive images in said second light sensitive material and transforming both prints into colored positives in colors complementary to the sensitivity of the layers of a multilayer light sensitive material which layers are complementarily dyed with respect to the color selections registered in the positive part images, selectively printing the colored positive prints in the'layers of the multilayer material, developing, and destroying the dyestui in the multilayer print at the points of the silver deposit to form dyestu images.

14. A method of producing color selection pictures from a subtractive multi-color image containing the individual color selection pictures in different colors which comprises printing with colored light absorbed substantially alone by the color of the part image to be printed ina light sensitive layer, developing and transforming the print into a dyestui image by coloring the exposed parts, printing with a dierently colored printing light absorbed by the colorof not only a second part image which it is intended to print but also to a lesser extent by the color of the i'lrst named part image of the multi-color image on a second multi-layer light sensitive material one layer of which is sensitized for light rays which are chiefly absorbed by the color of the second part image of the multicolor image and another layer of which is sensitized for light rays of a different spectral region said light rays.

being those chiefly absorbed by the dyestuff image in said iirst print, and printing said print of said first named part image into said last mentioned layer to produce an image' in said second light sensitive material which compensates for the undesirable image obtained therein as a result of the absorption of said second printing light by the color of said first part image of the multicolor image.

l5. A method of producing color selection pictures from a subtractive multi-color image containing the individual color selection pictures in different colors which comprises printing with colored light absorbed substantially alone-by the color of the part image to be printed in a light sensitive layer, developing and transforming the print into a dyestui image by coloring the exposed parts, printing with a differently colored printing light absorbed by the color of not only a second part image which it is intended to print the same degree but opposite gradation of opacity vas the disturbing image produced during the printing of said part image intended to be printed by reason of the overlapping absorption characteristics of said dyestuff images, and simultaneously developing the images in said printing material.

1'7. A method of producing color selection prints from a subtractive multi-color image containing each of the individual partial images as dyestui images indierent colors having overlapping absorption characteristics, which conn prises printing by means of a colored light which is mainly absorbed by the color of the part image intended to be printed into a printing material sensitized to this light, separately printing a partial image into said printing material with light e to which said printing material is sensitve from a compensating master image representing only a diierent part image of said multi-layer image.v

said partial image possessing the same degree but opposite gradation of opacity as the disturbing -image produced by said different part image of said subtractive multi-color image the color of which absorbs said rst mentioned printing light to a lesser extent and simultanebut also to a lesser extent by the color of the first named part image of the multi-color image on a second multi-layer light sensitive material one layer of which is sensitized for light rays which are chiefly absorbed by the color of the second part image of the multi-color image and another layer of which is sensitized for light rays of a different spectral region said light rays being those chiefly absorbed by the dyestuff image in said rst print, printing said print of said iirst named part imageinto said last mentioned layer to produce an image in said second light sensitive material which compensates for the undesirable image obtained therein as a result of the absorption of said second printing light by the color of said first part image of the multicolor image, and transforming said compensating image into a dyestufi image by coloring the exposed parts.

16. A method of producing color selection prints from a subtractive multicolor image containing each of the individual part images as dyestui images in diierent colors having overlapping absorption characteristics, which comprises printing by means of a colored light which is mainly absorbed by the color of the part image intended to be printed but due to said overlapping absorption characteristics is also absorbed to a lesser extent by the color of one or more additional part images into a printing material sensitized to this light, separately printing a partial image into said printing material. with light to which said printing material is sensitive vfrom a compensating master image vpossessing ously developing the images in said printing material.

18. A method of producing color selection prints from a subtractive multi-color image containing each of the individual partial images as dyestui images in different colors having overlapping absorption characteristics, which includes printing by means of a colored light which is mainly absorbed by the color of the part image intended to be printed into a printing material sensitized to this light, and which includes the steps of producing a compensating master image by printing Aan image of a second part image only, the color of Which absorbs said printing light to a lesser extent, into a diierent light sensitive printing material with a printing light mainly absorbed by the color of said second part i image, and separately printing into said flrstreferred to printing material with light to which Said printing material is sensitive from said compensating master image a partial image which possesses the same degree but opposite gradation of opacity as the disturbing image produced in said first referred to printing material by said second part image and simultaneously developing the images in said rst referred to printing material.

19. A method of producing color selection prints from a subtractive multicolor image containing each of the individual partial images as dyestuff images in different colors having overlapping absorption characteristics, which includes printing by means of a colored light which is mainly absorbed by the color of the part image intended to be printed into a printing material sensitized to this light and which includes the steps of producing a compensating master image by printing an image of a second` part image only, the color of which absorbs said printing light to a lesser extent, into a different light sensitive printing material with a printing light mainly absorbed by the color of said second part' material by said second part image, simultaneously developing the images in said first referred' to printing material, and converting said compensating master image, and the images -in said each of the individual partial images as dyestuif v images in different colors which have overlapping absorption characteristics, wherein an intermediate print'is produced of each of at least two partialimages contained in the multi-color mas ter image and is transferred-either directly or by way of further intermediate prints to the nal print, which includes the steps of printing a partial image of said multi-color Amaster image to form anrintermediate print in one layer of a multi-layer light sensitive printing material with a colored light to which said one layer is sensitive and which is mainly absorbed by the color of said part image but absorbed to a lesser' extent by another partial image, and separately printing an image of another partial image only into another layer lof said multi-layer printing material with light to which said other layer is sensitive to form a corrective print said corrective print having the same degree but opposite gradation of opacity as said other part image of said multi-color master image and being of suilicient density to correct for the undesirable image obtained in said one layer of said multi-layer printing material from said other part image and simultaneously developing the images in both of said layers.

21. A method of producing color selection pictures from a subtractive multicolor image containing the individual color selection pictures in different colors which comprises printing with colored light absorbed substantially alone by the color of the part image-to be printed in a light sensitive silver halide layer, developing the print thus obtained, printing with a differently colored printing light, absorbed by the color of not only a second part image which it is intended to print but also to a lesser extent by the color of the rst named part image, on a second light sensitive material and exposing the second printing material behind the uniixed print of the first named part image to produce an image in said second light sensitive material which compensates for the undesirable image obtained therein as a result of the absorption of said second printing light by the color of said iirst part image, dissolving the silver deposit from the unxed prints and developing again.

22, The method of producing a corrected color component image of a colored object by use of a photographic element having two sensitive layers permanently attached to a support, which comprises forming a negative age of one of the primary coloi` components o the colored object in one of the sensitive layers, forming a positive image of another of the primary color components of the colored object in the other sensitive layer, the positive image being superposed and in register with the negative image, and printing both images simultaneously to form a corrected color component-record of the colored object.

23. The method of making a correctedcolor selection image which comprises forming a strong and a weak image in two superposed emulsion4 developing one of said images as a negative and the other as a positive without separation of the layers.

24. The method of making a corrected color selection image which comprises forming a strong and a weak image in two superposed emulsion layers of diierent spectral sensitivities respectively, one of said layers being an ordinary negative emulsion and another layer being a direct positive emulsion, said images representing different color selections of a multicolor image and thereafter simultaneously developing both layers to provide a negative image in the rst layer and a positive image in the second layer.

25. The method of making a corrected color component image in a photographic element having two superposed silver halide layers, one of which contains a dye uniformly dispersed therein, which comprises forming in the layer not containing the dye a negative metallic silver image representing one of the primary color components of a colored object, forming in the layer containing the dye l a negative metallic silver image representing another primary color component of -thecolored object, bleaching the dye in the region of the last-mentioned negative image to form a positive dye image serving as a masking image and printing through the two images simultaneously with light of a color substantially complementary to the color positive dye image to form a corrected color component image representing the color complementary to that represented'by the negative image.

BLA GASPAR. 

